When another page is clicked, sometimes it comes up, and sometimes I get my 404 error. When the page loads fine, it does so quickly. But sometimes there are long load times and then I get the 404 error. When I get the 404 error, it seems nothing is really loading. I can see my theme and all, but in the sidebar, no info is loaded. As in no categories show up, no latest post, no nothing. I just have no content. This doesn’t just happen to sub-pages, because sometimes it happens if I’m on another page and click on ‘HOME’. It’s really quite annoying, any ideas where I can look for the problem?

I’ve also been getting something similar, also since back around 2.3. For example yesterday I went through my log files and pulled out every time a 404 error was issued back to a request. There were a few valid 404’s in there, but there were also quite a few requests for WP posts that ARE valid URLs, that the client was issued a 404 for.

It doesn’t happen very often, say five out of every 50,000 page views, but it DOES happen. I host about 25 other (non-WP) websites on the same server and I don’t see it happening on those sites, so it doesn’t appear to be a server config/Apache error.

How I noticed it was that WP had given my friend Googlebot a 404 for my homepage. Yikes! That isn’t good. Googlebot came back a few hours later and fetched the page fine.